All of the above plus...
Prime the
oil pump with the valve covers off (one at a time) and verify that the rocker shafts are getting
oil. I had a set of Edelbrocks in which the head stud for the
oil galley would pinch off supply when torqued down to spec completely cutting of the oil. Rare but I'm proof that it does/can happen. My restrictors are also from Gessfords. Best wishes!
Are your heads from Kieth Craft?